KR102019045B1 - Method for controlling coasting drive of environmentally friendly vehicle - Google Patents

Abstract

In another exemplary embodiment, a driving control method for a green vehicle includes determining, by a controller, a deceleration target speed of the green vehicle based on a forward deceleration event of the green vehicle, wherein the controller supplies a battery to supply power to a driving motor of the green vehicle. Determining a correction value of the charge limit amount, which is a value that prevents the charge limit for the battery, based on the charge limit amount for the battery and the accumulated charge amount for the battery according to the forward deceleration event; And controlling the eco-friendly vehicle to the deceleration target speed by performing hydraulic braking of the eco-friendly vehicle based on the correction amount of the battery charge amount and the charge limit amount.

Description

Off-road driving control method of eco-friendly vehicle {METHOD FOR CONTROLLING COASTING DRIVE OF ENVIRONMENTALLY FRIENDLY VEHICLE}

The present invention relates to a control method of a vehicle, and more particularly, to a traveling driving control method of an environment-friendly vehicle.

Eco-friendly vehicles include fuel cell vehicles, electric vehicles, plug-in electric vehicles, and hybrid vehicles, and typically include a motor for generating driving force.

An example of such an environmentally friendly vehicle, a hybrid vehicle uses an internal combustion engine and battery power together. That is, a hybrid vehicle uses a combination of the power of an internal combustion engine and the power of a motor efficiently.

The hybrid vehicle may be composed of an engine, a motor, an engine clutch that regulates power between the engine and the motor, a transmission, a differential gear, a battery, a starting generator that starts the engine or generates power by the output of the engine, and a wheel. have.

In addition, the hybrid vehicle may include a hybrid control unit for controlling the overall operation of the hybrid vehicle, an engine control unit for controlling the operation of the engine, a motor control unit for controlling the operation of the motor, A transmission control unit for controlling the operation of the transmission, and a battery control unit for controlling and managing the battery.

The battery controller may be referred to as a battery management system. The starting generator may be referred to as an integrated starter & generator (ISG) or a hybrid starter & generator (HSG).

The hybrid vehicle is an electric vehicle mode (EV) which is a pure electric vehicle mode using only the power of a motor, a HEV mode (hybrid electric vehicle mode) using a motor's rotational power as an auxiliary power while the engine's rotational power is a main power, and an automobile. When driving by braking or inertia, the vehicle may operate in a driving mode such as regenerative braking mode in which braking and inertia energy is recovered through generation of a motor and charged in a battery.

Matters described in this Background section are intended to enhance the understanding of the background of the invention, and may include matters other than the prior art already known to those skilled in the art.

The technical problem (object) to be solved by the present invention is to perform the deceleration control of the vehicle until the charge limit of the drive motor or the charge limit of the battery occurs, and a situation such as the charge limit of the drive motor or the charge limit of the battery is expected. When the hydraulic braking (or friction braking) to control the speed of the vehicle as a deceleration target to provide a way to control the running of the environment-friendly vehicle that can ensure the safety of the vehicle.

In order to solve (achieve) the above object, the traveling control method of the eco-friendly vehicle according to an embodiment of the present invention, the step of determining the deceleration target speed of the eco-friendly vehicle based on the forward deceleration event of the eco-friendly vehicle and The charging limit is a value that prevents the charging limit for the battery based on the charge limit amount for the battery supplying power to the driving motor of the eco-friendly vehicle and the accumulated charge amount for the battery according to the forward deceleration event. Determining a correction value of the amount, and the controller performs hydraulic braking of the eco-friendly vehicle based on the charge amount of the battery by the driving motor and the correction value of the charge limit amount, thereby driving the eco-friendly vehicle to the deceleration target speed. It may include the step of controlling.

The charging limit may be generated due to the performance of the battery or may be generated by the performance of the drive motor.

The determining of the correction value of the charge limit amount may include determining, by the controller, a correction value of the charge limit amount by using a value obtained by subtracting the accumulated charge amount of the battery from the charge amount of the battery. .

The step of controlling the eco-friendly vehicle to the deceleration target speed by performing hydraulic braking of the eco-friendly vehicle may include performing the hydraulic braking of the eco-friendly vehicle using the value obtained by subtracting a correction value of the charge limiting amount from the charge amount of the battery by the driving motor. Hydraulic braking of the vehicle can be performed.

The traveling driving control method of the eco-friendly vehicle further includes the controller determining whether the amount of charge of the battery by the drive motor is equal to or greater than a correction value of the charge limiting amount, and the amount of charge of the battery by the drive motor is increased. When it is determined that the charge limit amount is less than the correction value, the controller may operate the driving motor to control the eco-friendly vehicle at the deceleration target speed.

In the above-described traveling control method of an eco-friendly vehicle according to an exemplary embodiment of the present invention, energy recovery for battery charging is performed by performing active coasting by maximally utilizing a driving motor when a deceleration event occurs in front of the vehicle. And by following the deceleration target of the vehicle by using hydraulic braking when the battery charge limit or the charge limit of the motor can be increased the safety of the vehicle. The active regenerative braking is a braking that generates negative torque of the driving motor without mechanical braking, converts the potential energy into electrical energy to charge energy in the battery, and may mean regenerative braking with a predetermined target speed of the vehicle.

In order to more fully understand the drawings used in the detailed description of the invention, a brief description of each drawing is provided.
FIG. 1 is a view for explaining a deceleration target speed following of a vehicle due to a charge limitation on a battery caused by a drive motor.
2 is a view for explaining a deceleration target speed non-following condition of the vehicle due to the limitation of charging of the battery due to the battery.
FIG. 3 is a flowchart illustrating a method for controlling coasting of an eco-friendly vehicle according to an exemplary embodiment of the present invention.
4 and 5 are views for explaining the hydraulic braking shown in FIG.
FIG. 6 is a block diagram illustrating a hybrid vehicle to which the traveling driving control method of an eco-friendly vehicle according to an exemplary embodiment of the present invention is applied.

In order to fully understand the present invention and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings which illustrate embodiments of the present invention and the contents described in the accompanying drawings.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail by explaining embodiment of this invention with reference to attached drawing. In describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted. Like reference numerals in the drawings may refer to like elements.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, the terms “comprise” or “have” are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Throughout the specification, when a part is said to be "connected" to another part, it is not only "directly connected" but also "electrically or mechanically connected" with other components in between. Include.

Unless defined otherwise, the terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and shall not be construed in ideal or excessively formal meanings unless expressly defined herein. Do not.

There are various types of deceleration events of the vehicle during real road driving of the vehicle. There are deceleration events such as toll gates, IC (interchange) entry and exit, or speeding cameras on highway driving of vehicles, and decelerating events such as traffic signals or left / right turning of vehicles in urban driving of vehicles. (event) exists. The deceleration situation in front of the vehicle may be predicted in advance through the map information on the event in front of the vehicle and the update information on the real-time traffic situation. Therefore, in the case of an eco-friendly vehicle having a drive motor, the regenerative braking of the motor may be utilized by using the front information. By reaching the predetermined deceleration target by using the motor before reaching the deceleration event, it is possible to secure driving safety and recover energy through regenerative braking, thereby enabling fuel-oriented driving of the vehicle. However, as shown in FIG. 1 or FIG. 2, when the charging limit of the driving motor or the charging limit of the battery supplying power to the driving motor occurs, the braking using the driving motor cannot be performed, thus not following the deceleration target. The problem of not ensuring the driving safety of the vehicle may occur.

FIG. 3 is a flowchart illustrating a method for controlling coasting of an eco-friendly vehicle according to an exemplary embodiment of the present invention. 4 and 5 are views for explaining the hydraulic braking shown in FIG. FIG. 6 is a block diagram illustrating a hybrid vehicle to which the traveling driving control method of an eco-friendly vehicle according to an exemplary embodiment of the present invention is applied.

3 to 6, in the determining step 105, the controller 305 included in the hybrid vehicle 300 determines the deceleration target speed of the hybrid vehicle based on the forward deceleration event of the hybrid vehicle. Can be determined. The forward deceleration event may be provided to the controller 305 by a server installed (located) outside of the hybrid vehicle 300.

The forward deceleration event may include static traffic information, dynamic traffic information including traffic light information and traffic condition information. Static traffic information is high-precision map information including toll gate location, IC (interchange) location, road speed limit, vehicle left / right turn information, speed bump position, or speed camera location information. Can be. The traffic light information may include a signal change period, a green signal time, a red signal time, a red signal remaining time, a green signal remaining period, a remaining distance to the traffic light, or position information of the traffic light. The traffic situation information may include the number of vehicles for each road section, the distance for each road section, or the average speed of the vehicle for each road section.

The controller 305 may be, for example, one or more microprocessors operated by a program or hardware including the microprocessor, and the program may be configured to control the traveling of an eco-friendly vehicle according to an embodiment of the present invention. It may include a series of instructions for performing the method. The command may be stored in a memory (not shown).

The hybrid vehicle 300 may include a controller 305, an engine 310, an HSG 320, an engine clutch 325, a motor (or drive motor) 330, which may be an electric motor, Battery 340, transmission 350, and driving wheels 390 that are wheels.

The hybrid vehicle 300 is a hybrid electric vehicle, and may use the engine 310 and the motor 330 as a power source, and the engine clutch 325 between the motor 330 and the engine 310. Is present in the engine clutch 325 in the open state is operated in the electric vehicle (EV) mode driven by the motor 330, the engine clutch 325 in the closed state in both the motor 330 and the engine 310 It can be operated in a hybrid electric vehicle (HEV) mode that can be driven by.

The hybrid vehicle 300 may include a power train of a transmission mounted electric device (TMED) method in which the motor 330 and the transmission 350 are attached. The hybrid vehicle 300 may include an engine 310 and a motor 330. The engine clutch 325 is present between the power sources, and the EV mode or the engine, which is a pure electric vehicle mode using only the power of the motor 330, depending on whether the engine clutch 325 is engaged (engaged). It is possible to provide driving (driving) in a HEV mode (hybrid electric vehicle mode) using the rotational force of the 310 as the main power and the rotational force of the motor 330 as the auxiliary power. In detail, the motor 330 pulls the engine revolutions per minute (RPM) through the start of the hybrid start generator (HSG) 320 in the hybrid vehicle 300 having a structure directly connected to the transmission 350. Raised, power transmission and interruption of the engine 310 is carried out through the engagement (engagement) and separation of the clutch 325, the wheels (390) through a power train that may include a transmission (350) The driving force is generated, and when the torque transmission request of the engine 310 is requested, the engine torque may be transmitted through the bonding of the clutch 325.

The controller 305 may include a hybrid control unit (HCU), a motor control unit (MCU), an engine control unit (ECU), and a transmission control unit (TCU). have.

The hybrid controller (HCU) may control the starting (starting) of the engine through the control of the HSG 320 when the engine 310 is stopped. The HCU is a top-level controller that can collectively control controllers such as motor controllers (MCUs) connected to a network, such as a controller network (CAN), and control the overall operation of the hybrid vehicle 300. have.

The motor controller MCU may control the HSG 320 and the motor 330. The motor controller MCU may control the output torque of the driving motor 330 according to a control signal output from the hybrid controller HCU through the network so that the motor controller MCU may be driven to an area having maximum efficiency. The motor controller (MCU) includes an inverter composed of a plurality of power switching elements, and the power switching elements constituting the inverter include an IGBT (Insulated Gate Bipolar Transistor), a MOSFET, a FET, a transistor (TR), and a relay ( relay). The inverter may drive the driving motor 330 by converting a DC voltage (direct current voltage) supplied from the battery 340 into a three-phase AC voltage. The motor controller MCU may be disposed between the battery 340 and the motor 330.

The engine controller ECU may control the torque of the engine 310. The engine controller ECU may control an operating point of the engine 310 according to a control signal output from the hybrid controller HCU through the network so that the optimum torque may be output. The shift controller TCU may control the operation of the transmission 350.

The engine 310 may include any one of a diesel engine, a gasoline engine, an LPG engine, and an LNG engine, and outputs torque to an operating point according to a control signal output from the engine controller to drive the motor in the HEV mode. Can be appropriately maintained.

The engine 310 may generate power that is coupled to the motor 330 through the engine clutch 325 and transmitted to the transmission 350.

The hybrid starting generator (HSG) 320 operates as an electric motor or a generator, and operates as an electric motor according to a control signal output from the motor controller (MCU) to execute start-up of the engine 310 and the engine 310. ) Is operated as a generator in the state of maintaining the start-up to generate a voltage and provide the generated voltage to the battery 340 as a charging voltage through the inverter. The hybrid start generator (HSG) 320 may be connected to the engine 310 by a belt. The HSG 320 is a motor for cranking the engine 310, and may be directly connected to the engine or connected by a belt.

The engine clutch 325 may be disposed (mounted) between the engine 310 and the driving motor 330 to interrupt power transmission (power connection) so that the EV mode and the HEV mode may be provided. Operation of the engine clutch 325 may be controlled by the controller 305.

The driving motor 330 is operated by a three-phase AC voltage output from the motor controller (MCU) to generate torque, and operate as a generator in a coasting drive or regenerative braking to supply regenerative energy to the battery 340. Can be.

The battery 340 is composed of a plurality of unit cells, and for supplying a voltage to the driving motor 330 or the HSG 320 that provides driving force to the wheels 390, for example, a direct current 350 ( Volt) to a high voltage of 450V can be stored.

The transmission 350 may be implemented as a multiple speed transmission or a multistage transmission, such as an automatic transmission or a dual clutch transmission (DCT), and the hydraulic pressure according to the control of the transmission controller (TCU) By the operation of hydraulic pressure, the engagement element and the disengagement element can be operated to engage (select) any shift stage. The transmission 350 may transmit or block driving force of the engine 310 and / or the motor 330 to the wheels 390.

According to the decision step 110, the controller 305 is charged with a limit on the charge (or for the battery) and forward deceleration event (or the deceleration target) for the battery 340 that powers the drive motor 330. The correction value of the charge limit amount may be determined based on the charge accumulation amount (or the predicted charge accumulation amount) for the battery according to the speed). The correction value of the charge limit amount (or charge power limit amount) may be a value for preventing the charge limit for the battery 340.

The charge limit may be generated due to the performance (or specifications (hardware specification)) of the battery 340 or may be generated due to (or specifications (hardware specification)) of the driving motor 330.

The correction value of the charge limit amount shown in FIG. 4 may be changed according to a change in driving power of the hybrid vehicle 300 and may be determined by a test. The driving power may be a value obtained by multiplying the speed of the hybrid vehicle 300 by the driving torque of the hybrid vehicle.

For example, the correction value of the charge limit amount may be calculated (determined) by the controller 305 through the following equation.

Correction of charge limit = charge limit-cumulative charge

According to the determining step 115, the controller 305 may determine whether the charging amount (or the charging power amount) of the battery 340 by the driving motor 330 is equal to or greater than the correction value of the charging limit amount. have.

According to the calculation step 120, when it is determined in the determination step 115 that the charge amount of the battery 340 by the drive motor 330 is equal to or greater than the correction value of the charge limit amount, the controller 305 is driven. Hydraulic pressure is performed by the brake device (or hydraulic braking device) of the hybrid vehicle 300 by subtracting the correction value of the charge limit amount from the charge amount of the battery 340 by the motor 330. Can be determined by the amount of braking.

According to the control step 125, as shown in FIGS. 4 and 5, the controller 305 subtracts a correction value of the charge limit amount from the charge amount of the battery 340 by the drive motor 330. The hydraulic braking of the hybrid vehicle 300 may be performed using the value.

Explaining the calculation step 120 and the control step 125 in detail, the controller 305 is a hybrid based on the charge amount of the battery 340 by the drive motor 330 and the correction value of the charge limit amount. Hydraulic braking by the brake device of the vehicle 300 may be performed to control the hybrid vehicle at the deceleration target speed.

When the hybrid vehicle 300 is controlled at the deceleration target speed, regenerative braking may be performed. The regenerative braking recovers braking and inertial energy through the development of a driving motor driving the driving wheel of the hybrid vehicle when the hybrid vehicle is braking or inertia driven. It can mean doing. In detail, when there are traffic lights, curves, vehicles, and other objects in front of the vehicle, energy recovery may be possible through other driving without pressing the accelerator pedal and the brake pedal (coasting control). )).

According to the control step 130, when it is determined in the determining step 115 that the charge amount of the battery 340 by the drive motor 330 is less than the correction value of the charge limit amount, the controller 305 is driven. By operating (controlling) the motor 330, the hybrid vehicle 300 may be controlled (run) at the deceleration target speed.

The traveling control method for the eco-friendly vehicle according to the above-described embodiment of the present invention may be applied to an eco-friendly vehicle including the hybrid vehicle 300 and including a driving motor and a battery.

Components or “units” or blocks or modules used in the embodiments of the present invention may be implemented as software such as tasks, classes, subroutines, processes, objects, threads of execution, and programs performed in a predetermined area on the memory. Or a hardware such as a field-programmable gate array (FPGA) or an application-specific integrated circuit (ASIC), or a combination of the above software and hardware. The components or the 'unit' and the like may be included in a computer-readable storage medium, or a part thereof may be distributed and distributed in a plurality of computers.

As described above, the embodiments are disclosed in the drawings and the specification. Herein, specific terms have been used, but they are used only for the purpose of illustrating the present invention and are not used to limit the scope of the present invention as defined in the meaning or claims. Therefore, it will be understood by those skilled in the art that various modifications and equivalent embodiments are possible from the present invention. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

305: controller
330: motor
340: battery

Claims (5)

In the other traveling control method of the environment-friendly vehicle,
Determining, by the controller, a deceleration target speed of the green vehicle based on a forward deceleration event of the green vehicle;
The charge limit value is a value for preventing the charge limit for the battery based on the charge limit for the battery for supplying power to the driving motor of the eco-friendly vehicle and the estimated charge accumulation amount for the battery according to the forward deceleration event. Determining a correction value of the amount; And
Controlling, by the controller, the eco-friendly vehicle to the deceleration target speed by performing hydraulic braking of the eco-friendly vehicle based on a correction value of the battery charge amount and the charge limit amount by the driving motor;
Including,
Determining a correction value of the charge limit amount,
Determining, by the controller, a correction value of the charge limit amount using a value obtained by subtracting a predicted charge accumulation amount for the battery from the charge limit amount for the battery;
The hydraulic braking of the eco-friendly vehicle is performed to control the eco-friendly vehicle at the deceleration target speed.
And the controller performs the hydraulic braking of the eco-friendly vehicle by using a value obtained by subtracting a correction value of the charge limit amount from the charge amount of the battery by the driving motor. The method of claim 1,
The charging limit amount is generated due to the performance of the battery or other driving control method of the eco-friendly vehicle, characterized in that generated by the performance of the drive motor. delete delete The method of claim 1, wherein the other driving control method for the eco-friendly vehicle includes:
And determining, by the controller, whether the charge amount of the battery by the drive motor is equal to or greater than a correction value of the charge limit amount.
When it is determined that the charge amount of the battery by the drive motor is less than the correction value of the charge limiting amount, the controller operates the drive motor to control the eco-friendly vehicle at the deceleration target speed. Driving control method.

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